The relation between the number of parasites/host and host age: population dynamic causes and maximum likelihood estimation | Parasitology | Cambridge Core (original) (raw)

Summary

We examined dynamical factors that shape the distribution of the number of parasites/host in constant or temporally varying environments, and with or without host-age dependent variation in host susceptibility and parasite mortality. We predict properties of the parasite distribution in the absence of density-dependent factors such as densitydependent mortality or recruitment and parasite-induced host mortality. These properties provide a criterion for the detection of density dependence in temporally variable systems with host-age dependent interactions. We have then introduced methods to estimate and statistically evaluate the effects of host age or size on the distribution of parasites/host. The methods are based on a maximum likelihood protocol for linear and non-linear regression when data are negatively binomially distributed. We have illustrated the use of the theoretical results and statistical methods by re-analysing the data of Halvorsen & Andersen (1984) on cestode infections in Norwegian arctic charr and by analysing new data on nematode infections in Caribbean Anolis lizards.

References

Adjei, E. L., Barnes, A. & Lester, R. J. G. (1986). A method for estimating possible parasiterelated host mortality illustrated using data from Calliterarhynchus gracilis (Cestoda: Trypanorhyncha) in lizard fish (Saurida) spp. Parasitology 92, 227–43.Google Scholar

Anderson, R. M. (1982). Epidemiology of infectious disease agents. In Modern Parasitology (ed. Cox, F. E. G.), pp. 204–51. Oxford: Blackwell Scientific Publishers.Google Scholar

Anderson, R. M. & Gordon, D. M. (1982). Processes influencing the distribution of parasite numbers within host populations with special emphasis on parasite-induced host mortalities. Parasitology 85, 373–98.CrossRefGoogle ScholarPubMed

Anderson, R. M. & May, R. M. (1978). Regulation and stability of host-parasite population interactions. I. Regulatory processes. Journal of Animal Ecology 47, 219–48.Google Scholar

Anderson, R. M. & May, R. M. (1979). Population biology of infectious diseases. I. Nature, London 280, 361–7.Google Scholar

Anderson, R. M. & May, R. M. (1985). Helminth infections of humans: mathematical models, population dynamics, and control. In Advances in Parasitology, vol. 24, pp. 1–101. London: Academic Press.Google Scholar

Crofton, H. D. (1971 a). A quantitative approach to parasitism. Parasitology 62, 179–179.Google Scholar

Crofton, H. D. (1971 b). A model of host-parasite relationships. Parasitology 63, 343–343.CrossRefGoogle Scholar

Dietz, K. (1982). Overall population patterns in the transmission cycle of infectious disease agents. In Population Biology of Infectious Diseases (ed. Anderson, R. M. and May, R. M.), pp. 87–102. Berlin: Springer-Verlag.Google Scholar

Dobson, A. P. (1985). The population dynamics of competition between parasites. Parasitology 91, 317–47.Google Scholar

Gordon, D. M. & Rau, M. E. (1982). Possible evidence for mortality induced by the parasite Apatemon gracilis in a population of brook sticklebacks Culaea inconstans. Parasitology 84, 41–41.CrossRefGoogle Scholar

Halvorsen, O. & Andersen, K. (1984). The ecological interaction between arctic charr, Salvetinus alpinus (L.), and the plerocercoid stage of Diphyllobothrium ditremum. Journal of Fish Biology 25, 305–305.CrossRefGoogle Scholar

Kennedy, C. R. (1984). The use of frequency distributions in an attempt to detect host mortality induced by infections of diplostomatid metacercariae. Parasitology 89, 209–20.Google Scholar

Lester, R. J. G. (1984). A review of methods for estimating mortality due to parasites in wild fish populations. Helgolander Meeresunters 37, 53–64.Google Scholar

May, R. M. (1977). Dynamical aspects of host-parasite associations: Crofton's model revisited. Parasitology 75, 259–76.CrossRefGoogle Scholar

May, R. M. & Anderson, R. M. (1978). Regulation and stability of host-parasite population interactions. II. Destabilizing processes. Journal of Animal Ecology 47, 249–68.Google Scholar

May, R. M. & Anderson, R. M. (1979). Population biology of infectious diseases. II. Nature, London 280, 455–01.Google Scholar

Pacala, S. W. & Roughgarden, J. D. (1985). Population experiments with the Anolis lizards of St Maarten and St Eustatius. Ecology 66, 129–51.CrossRefGoogle Scholar

Pielou, E. C. (1977). Mathematical Ecology. New York: John Wiley.Google Scholar